Showing papers on "Image sensor published in 1978"

Color Imaging System Using a Single CCD Area Array

Abstract: A color imaging system employing a single CCD sensor with a color filter array has been implemented. The system incorporates color channel enhancement and interpolation and provides display on a conventional color video monitor. Color correction matrix coefficients are computed. The response of the system is compared to that of a photographic film.

Apparatus and method of personal identification by fingerprint comparison

Abstract: Finger prints of authorized personnel are initially stored in digital form in a memory. Subsequently, personal identification is obtained by matching the fingerprints of individuals with the stored prints. The individual places his finger in an activator which indexes the finger and turns on the equipment. The fingerprint image may be refleted directly into an electronic image sensor or it may be initially impressed upon a tape for later image scanning. In either case, the electronic image sensor scans the fingerprint image and converts the optical characteristic of the print into a plurality of picture elements, and provides an electrical signal representative of each of the picture elements at its output. The picture elements are converted either in the electronic image sensor or in an analog to digital converter into a digital code representative of each picture element. These digital codes are entered into a temporary storage for comparison with the fingerprints contained in the memory. Handshaking circuits cause the image fingerprint to be compared with each stored fingerprint until either a match is obtained or the image has been compared with each print contained in the memory and no match was made. The match or no-match condition causes, respectively, a go or no-go output indication which may be used to perform any number of desired functions.

Holographic playback system using a charge storage sensor and binary decoding

Abstract: A holographic playback system comprises a turntable adapted to support a record disk which contains a series of holograms recorded along convoluted spiral tracks. Each of the holograms represents a pattern of data bits and synchronization bit, and an optical system for directing a laser beam to the record disk, whereby the laser beam is diffracted by the interference fringes of the hologram to reconstruct the image of the pattern of data and synchronization bits. The turntable is driven so that the holograms are successively shifted in location with respect to the laser beam and illuminated by the beam. A solid-state image sensor is provided which includes a plurality of charge storage type sensing elements each positioned to receive the reconstructed image of each data bit and a non-charge storage type sensing element positioned to receive the reconstructed image of the synchronization bit. The charge storage type image sensing elements is sequentially triggered to generate a series of binary signals before a subsequent hologram is shifted to the beam-illuminated position. The binary signals are then decoded into the original signal for reproduction. The speed of the turntable is controlled in accordance with the reproduced synchronization signal.

Solid state television camera with noise eliminating circuit

Abstract: A solid state television camera with a noise eliminating circuit includes a solid state image sensor of semiconductor material to provide an output signal in correspondence to the image of an object projected thereon; a memory to memorize the positions of crystal defects in the semiconductor material; and a control circuit responsive to the output of the memory for eliminating from the output signal of the solid state image sensor noise due to crystal defects in the semiconductor material. The position of the first of the crystal defects encountered in the raster is determined by the distance, measured either along the successive scanning lines or along the orthogonal axes of the raster, between a reference point and such first crystal defect and that distance is encoded and memorized in the memory. The position of any other crystal defect is determined by the similarly measured distance between such other crystal defect and the crystal defect prior thereto, which distance is also encoded and memorized in the memory.

Fabrication and Performance of Color Filter Arrays for Solid-State Imagers

Abstract: A technique has been developed for the fabrication of a color filter array (CFA) to be used in conjunction with a solid-state area sensor to provide three-color image information from a single sensor. The fabrication technique employs sublimable dyes which are heat-transferred through photoresist windows onto a polymer receiving layer. Good edge sharpness and a low dye penetration depth into the polymer have been achieved. The predicted and measured spectral response of the color channels of the composite device are in good agreement. The pattern noise associated with CFA transmittance fluctuations from element to element is on the order of 10 percent.

Correlation follower for tracking an object

Abstract: A correlation follower comprising an image sensor (1) adjustable sideways and in height with a limited field of view, which is cyclically scanned by the sensor the output signal of which reflects the image content within the field of view and a video correlator (3) for controlling the alignment of the sensor in dependance of the output signal of the image sensor. The video correlator (3) has two addressable memories (12, 14) the one of which is a real time memory (12), i.e. in this memory a section of the field of view is stored for each cycle. The other memory is a reference image memory (14) and is updated with the content or the real time memory (12). During the correlation the contents of the memories are displaced in relation to each other and an error signal, corresponding to the position of displacement for which maximum correlation is achieved, is made to control, through said control circuits, the alignment of the sensor. To make the tracking process insensitive to disturbancies and image elements which appear momentarily in the field of view for each scanning cycle only a part of the positions of the reference image memory (14) are updated by selection the addresses to said positions randomly or according to a predetermined rule of selection. By that the positions which are updated during one cycle in positions are distributed over the entire area of the memory.

Synthetic aperture using image scanner

Abstract: In a system for generating a synthetic aperture, a lens or antenna for focusing the radiation from an object scene onto an image sensor which is shifted by a clock at the rate of motion of objects in the object scene and thereby to produce the real tire imaging of the object scene with high resolution. A system for reconnaissance, surveillance and ground mapping. A system for high speed data imaging, medical patient scanning, label scanning, and image correlation.

Computer-aided tracking of body motions using a c.c.d.-image sensor.

Abstract: A c.c.d-image sensor has been used to obtain virtually online trajectories of moving objects in one plane. The image data acquired are stored and processed by several programs to yield displays which enable interpretation and measurement to be effected. Our major concern is in regard to kinesiological data allied with human locomotor function.

Defect noise compensating system

Abstract: A solid state television camera which is free from the noise caused by defects in semiconductor substrate is disclosed. A solid state image sensor having a plurality of picture elements aligned in vertical and horizontal direction is provided to derive a picked up output signal. A memory device is also provided which has a plurality of memory cells of the same arrangement as the image sensor. A mask is provided in front of the memory device, and the mask has an opaque pattern upon receipt of a light corresponding to a defect position of the image sensor. The image sensor and the memory are driven simultaneously, and the reading out of the signal from the image sensor is controlled by the readout signal from the memory which is corresponding to the defect position of the image sensor.

An Experimental Telecine Using a Line-Array CCD Sensor

Abstract: Conventional telecine equipment uses either camera tubes or flying-spot cathode-ray tubes to analyze the film image. Both methods can produce excellent results but suffer from a number of basic problems. Electron beam deflection and focusing always involves some compromises with uniformity of focus and other aberrations of the scanning spot, and both camera tubes and flying spot tubes introduce other signal distortions such as image lag and afterglow effects. A slow deterioration of performance is also inevitable as tubes age and regular replacement and realignment is necessary. With the advent of CCD (charge-coupled-device) technology and its application to solid-state image sensors, it is now possible to consider using such sensors for scanning film to produce pictures of full broadcast standard. This paper describes the progress that has been made towards achieving an all-solid-state telecine. The stage has now been reached where it is possible to produce excellent quality 625-line, 50-fields/s monochrome pictures with a 1024-element array, and color operation is being implemented.

Output correcting system for facsimile

Abstract: An optical image reading apparatus comprises a solid state image sensor having a plurality of blocks, means for generating video signals correponding to an object to be read out by the solid state image sensor, means for determining respective mean values of the video signals concerning the blocks, means for storing the mean values in digital information, means for reading out the stored mean value and converting the digital information to analog information, and means for determining a corrected slice level in each of the blocks.

A multiple-gate CCD-photodiode sensor element for imaging arrays

Abstract: The addition of barrier and storage gates between the photodiodes and transfer gates of a CCD imaging array provides improved and versatile operating characteristics compared with present silicon scanners. An experimental scanner, made with multiple-gate photoelements, has new functional capabilities which result from the on-chip structure. These include exposure control in real-time which can compensate for temporal illumination variations during the integration cycle, linearization of the output signal with respect to light intensity, and adaptive level setting to normalize the output based on the whitest portion of the image. Complete charge transfer into the shift register is achieved at reduced shift-register voltages. The use of photodiodes and the absence of polysilicon in the photosensitive region improve spectral response and overall sensitivity. A sixteen element 4-phase, 2-level polysilicon CCD imager was designed, fabricated, and used to test the improved photoelement structure.

The resistive gate CTD area-image sensor

Abstract: The transport of charge in a resistive gate controlled PCCD channel structure is described. With the aid of time analysis it is shown that this structure can be used for column transport in a practical area-image sensor. The operating principles of this type of CTD sensor are discussed, with emphasis on blue sensitivity and antiblooming operation. A 96-element linear test circuit has been built for evaluating the expected sensor performance. Design data and some relevant measured results are presented. Results for charge transport time, modulation transfer function, and spectral responsivity illustrate the feasibility of this new solid-state sensor approach.

A Meander Channel CCD Linear Image Sensor

Abstract: A new type of 1024-element linear image sensor has been developed using a CCD with a meander channel (MCCD). Its simple electrode pattern with no contact windows for clocking promises high yield in the production.

MTF Simulation Including Transmittance Effects and Experimental Results of Charge-Coupled Imagers

Abstract: A modulation transfer function (MTF) model for front-illuminated charge-coupled imagers (CCI's) which takes into account the periodically varying light transmittance of the photoelement array surface is derived. An inexpensive direct MTF measurement technique for CCI's was developed and is described. Experimental MTF measurements confirm the complete MTF model. Spatial resolution measurements and MTF simulation results of practical CCI photoelement array structures show that the periodically varying surface-light transmittance of the photoelement array contributes significantly to the behavior of the overall MTF and aliasing of the imager.

Survey Of The Present State Of The Art In Applications Of Solid-State Image Scanners

Abstract: The industrial uses of solid -state image sensors, such as photodiode, CCD and CID arrays,are reviewed. The case studies to be presented in these proceedings are supplemented byexamples of and reference to further significant applications in the areas to be covered.Brief descriptions are also given of applications in other major areas. Some generaltechniques of optics and signal processing which are used when building arrays intoinstrumentation systems are also described.IntroductionNo -one given the task of reviewing the applications of solid -state image scanners canhope to include all the relevant examples, because the field is so wide. Any task which isor can be performed optically, and which needs to be done faster, more accurately, moreconsistently or more conveniently than can be done by a human operator, provides a possibleapplication for electro- optical instrumentation. Photodiode and CCD arrays are applicablein a large number of these cases. The range of applications can be classified into thebroad groups described below. Prominent examples of each type of application are given,and some of the basic techniques used in building arrays into systems are described alongthe way.Simple gaugingThis group of applications is so called not because the design of the instrumentation isnecessarily simple, but because the measurement of a single dimension is fundamentally thesimplest and most obvious application for linear arrays of photodetectors. Examples areequally obvious and include measurement of the width of webs', the diameter of rods andfibres

A Multiple-Gate CCD-Photodiode Sensor Element for Imaging Arrays

Abstract: The addition of barrier and storage gates between the photodiodes and transfer gates of a CCD imaging array provides improved and versatile operating characteristics compared with present silicon scanners. An experimental scanner, made with multiple-gate photoelements, has new functional capabilities which result from the on-chip structure. These include exposure control in real-time which can compensate for temporal illumination variations during the integration cycle, linearization of the output signal with respect to light intensity, and adaptive level setting to normalize the output based on the whitest portion of the image. Complete charge transfer into the shift register is achieved at reduced shift-register voltages. The use of photodiodes and the absence of polysilicon in the photosensitive region improve spectral response and overall sensitivity. A sixteen element 4-phase, 2-level polysilicon CCD imager was designed, fabricated, and used to test the improved photoelement structure.

A Device Structure and Spatial Spectrum for Checker-Pattern CCD Color Camera

Abstract: In order to develop practical color cameras with useful resolution, a novel image processing and charge-coupled device (CCD) structure is proposed which results in shrinking chip size and easing photolithography. The resolution of CCD cameras is limited by the aliasilrng errors associated with spatially discrete sampling on a photosensing area. The photosensing array arranged in a two-dimensional face-centered rectangular lattice scheme, and the spatial offsetting technique among three CCD's avoid undesirable signal carriers accompanied by aliasing errors. A unique signal processing about vertical correlation of an image is put to use, in order to reduce spurious effects of aliasing. These image processing techniques are theoretically treated on a spectrum space. The photosensing array arranged in a face-centered rectangular lattice scheme is successfully implemented with a zigzag-transfer CCD with checker-pattern sensing sites, which relax some of the lithography requirements and improve image qualities. By means of the zigzag-transfer CCD structure and the image processing, the resolution of color camera has been expanded by a factor of 2.5, compared with that of the conventional CCD cameras employing the same number of pixels. According to the theory, the factor may be increased further up to three or four.

Imaging state detecting system of image

Abstract: PURPOSE: To surely detect the imaging state of images by comparing the scanning signals of the images formed by an image forming optical system and evaluating the imaging state from the differences in the illuminances of the proximate two positions of the images. CONSTITUTION: The images formed by an image forming optical system 1 are scanned by a semiconductor image sensor 4 such as of BBD photo diode array or the like provided at the intended focal plane or in the position conjugate with said focal plane. At this time, the time-series scanning signals and the scanning signals scanned immediate before going through a delay circuit 7 are applied to a differential amplifier 8 whereby they are made to differential signals which are then held in a holding circuit 12 by way of an absolute value circuit 8, γ converting circuit 10 adding specified weights, integrating circuit 11, etc. and are displayed in a display meter 13. Hence, the illuminance differences of the proximate two positions of the images for the image state are evaluated by the meter 13 and the imaging state of the images may be detected surely. COPYRIGHT: (C)1980,JPO&Japio

Manufacture of semiconductor device

Abstract: PURPOSE:At two specific parts on a semiconductor pellet, the electromagnetic-wave generative source of an isotope or the fluorescent dye are coated, and the coordinate expressing the position of a pellet surface pattern is obtained by an image sensor, so that this will be given to the automatic bonding equipment as the XY coordinate and the correction data of the difference in angle.

A Contact Type Linear Photodiode Array Using an Amorphous Thin Film

Abstract: A Contact type linearly arrayed imaging sensor not requiring an optical lens system has been successfully developed. This sensor array consists of 40 amorphous Saticon type photodiodes formed on an optical fiber plate, each of which measures 250 µm by 200 µm and the overall sensor length is 10 mm. This device has an advantage of easy fabrication which permits elongation of the total length without deteriorating the high resolution characteristics. Therefore, it may be useful as an imaging sensor for small size facsimile equipment. In this paper, a series of technical data on the proposed structure, the fabrication procedures and also the static and operational performances are described.

Signal readout in CID image sensors

Abstract: An analysis is presented that relates the photogenerated charge collected in one element of a charge-injection device imaging array to the voltage readout corresponding to that element. A linear relationship results when a voltage sensing amplifier is used. Crosstalk is found to occur, however, when a portion of the array is illuminated above saturation. This effect was demonstrated in a CID imager. A charge-amplifier scheme is presented that eliminates this type of crosstalk as well as some fixed pattern noise.

Automatic focusing device

Abstract: PURPOSE: To make possible focusing of high accuracy by making the image sensor outputs for in-focusing and out-focusing accurately symmetrical with respect to the imaging point. CONSTITUTION: Out of the reflected light from the material 4 to be observed, the one having passed through a beam slitter 5 images at A and the one reflected does at A'. An image sensor 6 for out-focusing is placed in the position backward l from A and an image sensor 7 for in-focusing in the position forward l' from A'. The differential signal of the effective value outputs comprising taking out the electric signals from the image sensors 6, 7 respectively with their high frequency components and integrating them for the specified period is taken out in a differential amplifier circuit 16 and is then fed back to a servo motor 17 which in turn drives a stage elevating handle 2, whereby the automatic focus control is made possible. COPYRIGHT: (C)1980,JPO&Japio

A High Resolution Solid State Charge Coupled Device (CCD) Space Borne Earth Imager

Abstract: A solid state (Charge Coupled Device) imaging system is described which satisfies the requirement for multispectral, high resolution, real time imagery. The system, using an earth resources survey satellite as its platform is configured to yield a 10 meter ground resolution with a 50 kilometer swath width at approximately 1000 km altitude. Four spectral bands ranging from 0.5 to 1.1 μm have been selected and are implemented by optically butting three 1728 pixel linear arrays (5184 pixel per band) on appropriate beam splitting prisms. The device employed, the Fairchild CCD 121H, shown in Figure 1, is a monolithic self-scanned image sensor utilizing two phase, buried n-channel CCD technology. The device has an element-to-element pitch of 13 μm (approximately 2000 pixel inch) and has been demonstrated to have a wide dynamic range (2500:1), Figure 2, low noise equivalent exposure and dimensionally precise photosite spacing. Consideration of focal plane design, geometric accuracy, image registration, temperature control, optical design, and noise figures are discussed. Particular emphasis has been placed on the unique properties of CCD detectors which allow for specialized post processing of the video for dealing with low contract scenarios. The paper concludes with new trends in specialized time delay and integration (TDI) mode imaging systems now under study and development at Fairchild.© (1978) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The Dynamic Sampling Effect With Charge-Coupled Device (CCD) Imagers

Abstract: Using CCD and CID image sensors, the array of detector elements performs a spatial sampling, which sets a maximum limit (Nyquist frequency) on the spatial resolution. In some sensors the MTF is high at and beyond the Nyquist frequency. By moving the sensor relative to the scene it is possible to obtain samples in between the stationary sampling positions. Thereby, the maximum spatial frequency limit is increased. This paper describes measurements with a CCD image sensor using this dynamic sampling effect. Resolution up to 3.5 times the Nyquist limit is shown. A theoretical calculation of expected obtainable MTF's for different sets of parameters is presented. This can be used to select parameters for best possible result when using the dynamic sampling effect.

Light scanning method

Abstract: PURPOSE:To process the correction of scanning distortions in real time and have scanning performed by disposing an image sensor in the position immediate before the modulating light moving on the surface being scanned reaches effective scanning region.

Automated Surface Inspection With Solid-State Image Sensors

Abstract: The application to automated surface inspection of solid-state imaging devices, such as photodiode arrays and charge coupled devices (CCD), is discussed in relation to the other forms of electro-optical inspection systems, and the advantages and disadvantages highlighted. A specific application is described, in which a camera containing a 512 element photodiode array has been used to inspect the width and surface quality of a narrow metal strip used in the manufacture of submarine cable.© (1978) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The Resistive Gate CTD Area-Image Sensor

Abstract: The transport of charge in a resistive gate controlled PCCD channel structure is described. With the aid of time analysis it is shown that this structure can be used for column transport in a practical area-image sensor. The operating principles of this type of CTD sensor are discussed, with emphasis on blue sensitivity and antiblooming operation. A 96-element linear test circuit has been built for evaluating the expected sensor performance. Design data and some relevant measured results are presented. Results for charge transport time, modulation transfer function, and spectral responsivity illustrate the feasibility of this new solid-state sensor approach.

Signal Readout in CID Image Sensors

Abstract: An analysis is presented that relates the photogenerated charge collected in one element of a charge-injection device imaging array to the voltage readout corresponding to that element. A linear relationship results when a voltage sensing amplifier is used. Crosstalk is found to occur, however, when a portion of the array is illuminated above saturation. This effect was demonstrated in a CID imager. A charge-amplifier scheme is presented that eliminates this type of crosstalk as well as some fixed pattern noise.